Can the Pope and the Patriarch Make Peace?

On Sunday, Roman Catholic and Eastern Orthodox churches -- which follow different liturgical calendars -- will both celebrate Easter, a convergence that may mark the beginning of a new era for the two churches, which split in 1054, the same year Macbeth was defeated at Dunsinane. They spent the next 910 years turning their backs on one another, until a Pope (Paul VI) and a Patriarch (Athenagoras) met in Jerusalem to begin patching things up.

But as Lady Macbeth taught us: "What's done cannot be undone." Or can it?

Next month, the head of each church -- Pope Francis and Patriarch Bartholomew I -- will gather in Jerusalem to mark the 50th anniversary of the historic meeting, which led to a joint statement of reconciliation at the Second Vatican Council in 1965. The statement expressed mutual forgiveness and a desire for a return to full communion, with members of each church fully participating in each other's liturgies.

Relations have continued to improve since, particularly in recent years. Last year, Bartholomew I became the first Patriarch to attend the inaugural mass of a new Pope since the churches split, and Francis has signaled that bringing the two "sister churches" closer together will be a priority.

One of Francis's fellow Jesuits, Robert F. Taft, is an American scholar who spent 45 years in Rome working to build bridges between the eastern and western churches. He has argued that the biggest issues dividing the churches are not doctrinal -- though those differences exist -- but behavioral. Church leaders must learn how to "emphasize the common tradition underlying our differences, which, though real, are usually the accidental product of history, culture, language, rather than essential differences in the doctrine of the common, apostolic faith."

Part of this process requires that each side acknowledge its sins, a core act of Christianity. "It is a contest in reverse," he says. "A contest of Christian love, one in which the parties seek to understand and justify not their own point of view," but the other's.

Bartholomew I has long been committed to the reconciliation process, and there has never been a Pope more suited to this work than Francis. In addition to his back-to-basics theology, which involves a humility so inspiring it is chasing bishops out of their mansions, Francis has spoken glowingly of the Eastern Orthodox Church's collegial approach to governance: "Their vision of the Church and synodality is marvelous."

Synods gather church leaders together to consider major issues. In October, Francis is convening a synod on the family, and among the issues to be taken up will be the church's relationship with divorced and cohabitating couples. Second marriages and pre-marital sex are both considered grave sins under Catholic teaching, and those who commit them are prohibited from receiving Communion. Remarried Catholics generally follow the rule; to do otherwise is to risk priestly rebuke and accusing stares. But most young Catholics who engage in premarital sex ignore the rule, if they are even aware that they fall under it.

The act of Communion -- sharing consecrated bread and wine -- is the foundation of the Catholic mass. Excluding remarried Catholics from participating in it is a severe punishment that can isolate those who need healing. A murderer who seeks forgiveness can be welcomed back into Communion, but a battered woman who remarries to help support her children cannot, unlike in the Eastern Orthodox Church, which generally permits remarriages that are accompanied by penance, as an act of mercy.

Francis seems intent on healing the Church's wounds, internally and externally. Doing so is a monumental task, and most observers expect change to come slowly and incrementally, if at all. Then again, few expected the transformational changes that emerged from the Second Vatican Council.

If Francis and Bartholomew I are able to fulfill Vatican II's ecumenical vision by moving their two flocks into full communion with one another, they will achieve a historic advance for Christian unity -- and for the belief that Holy Communion is an act of shared faith among sinners seeking God's love and forgiveness, not a privilege that can be forever rescinded.

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Corrects first paragraph to remove inaccurate reference to Easter convergence next year.